The publication "Horizontal Well Logging by `Symphor` (Eighth European Formation Evaluation Symposium, London, 1983) describes a borehole-logging method and the corresponding apparatus particularly directed at logging horizontal or slant boreholes by a logging probe on the end of the drill string and a logging cable extending between the drill string and logging cart on the surface and movable by a cable winch. The logging probe comprises a massive rod mechanically and electrically connected with the cable shoe and to which a coupling rod is connected which is connected behind the logging tools. The probe furthermore has a coupling housing for connection to the drill string and a protective housing for the logging tools and having an aperture. With this telemetry method and with the corresponding apparatus there is the disadvantage that the logging probe is fixed on the drill string so that the drill string must be taken apart before every logging in order to take the bit off the lower end of the drill string and to install the logging probe there.
Furthermore from "Efficiently log and perforate 60.degree.+ wells with coiled tubing" (World Oil, July 1987, pp. 32, 33, and 35) a method and a telemetry apparatus are known wherein instead of the drill string a special windable hose is used with a special hose winch and on whose end a logging probe, for example a gamma-ray probe, is connected as a locating probe for casing joints or as an acoustic sound for checking the annular cement joints between the casing and the surrounding rock. With this telemetry method and the apparatus for carrying it out it is possible to do a quick check of such bores after the derrick has been removed. On the other hand it is disadvantageous that one must use a special winch and a special hose string in order to make the necessary loggings.